Seam sealer is applied to joints to prevent what?

• A. Moisture intrusion
• B. Air leakage
• C. Noise
• D. UV fading

Answer: (A)

Moisture intrusion is prevented by seam sealer. The seams where body panels and components meet create gaps that water can seep through and enter the hollow cavities of the car. If water gets behind panels, it can lead to rust, corrosion, and electrical problems, as well as potential damage to insulating materials and interior trim. Sealing these joints with seam sealer forms a flexible, waterproof barrier that blocks water from entering those hidden spaces, helping protect the body from corrosion over time. While reducing air leakage and wind noise can be a beneficial side effect, the primary purpose is to keep moisture out. UV fading isn’t addressed by seam sealer, which is why it isn’t the correct focus here.